1. Field of the Invention
This invention refers generally to an apparatus for transferring weight stress and loading from the lumbar spine to a rib cage of an individual to obtain benefits associated with unloading the spine. More specifically, this invention relates to a fluid filled bladder for use as a seat whereby the amount of stress transferred may be adjusted by adding or removing fluid from the bladder.
2. Description of the Prior Art
Back pain is a common and significant malady afflicting large numbers of people and virtually every country of the world. The wide spread nature of the problem has been highlighted in numerous articles printed in both medical and new periodicals. Illustrative are articles entitled Bare-bones Facts About Your Aching Back from the December, 1980 issue of Readers Digest and the cover story from Jul. 14, 1980 issue of Time magazine.
Axial traction has been shown to be effective in treating certain types of low back ailments, in preventing back ailments and in producing and sustaining low back health. Such traction has been found to be an effective means of realigning improperly aligned or displaced vertebral elements as well as their associated invertebral discs and soft tissues. Such traction when used periodically for sustained periods has also been shown to reduce herniated contained intervertebral discs. Further, such traction has also been shown (in muscle and ligament injury or insult) to reduce spasm and inflammation, enhance blood flow and to promote optimal healing. Certain circumstances have, however, long presented obstacles to the effective application of controlled traction to the lumbar area. These circumstances include the significant amount of force which must be applied, the lack of a location at which the axially directed force can be applied, and the position of the person during which the axial force is being applied.
In 1971, Charles Burton, M.D. provided for the construction of an apparatus to support a person, such person having one of a number of conditions such as a protruded lumbar disc, in a vertical position wherein the torso of the person was suspended from above by a chest harness and vest encircling the rib cage. As a result of related research and experience it has been demonstrated scientifically and conclusively that the rib cage can serve as an optimum site of fixation and does serve well this purpose. In order for the overhead harness vest to function most effectively, it was observed that it should, at its lower end, be tightened beneath the rib cage so that, as axial force is applied by the body's weight to the harness, the rib cage will not slide out of the harness of vest.
After continued research, an improved gravity traction vest was developed. Prior to this time, the tightening of a lower most belt of the gravity vest was accomplished exclusively by providing a belt having a sufficient number of locking points whereby the belt could be tightened so that it was within the perimeter of the rib cage regardless of the size of the person being treated. The new improved gravity traction vest (shown in U.S. Pat. No. 4,422,452) provided means whereby axial fixation could be efficiently accomplished, yet wherein the treatment is not rendered uncomfortable.
While the improved second generation gravity traction vest provided improvement over the original gravity traction vest, there remained a number of problems associated with its use. Their problems included the need to tighten a number of cinctures to secure the vest to the person, the rough surfaces of the cinctures being felt through the vest by the person. While there was an improved locking of the vest to the person due to a cushion insert, it was desirable to provide for still more positive locking. The need to provide improved comfort to the persons has always been a goal which each new generation of product has tried to accomplish. The goal was to provide a vest which allowed the person to experience gravity traction without causing unnecessary discomfort. While there has been improvement in this area, there has been the need for still more improvement.
It is these problems in the prior art that a third generation gravity traction vest was developed. It provides for a torso surrounding member being constructed of a rigid material, a simple and effective means for securing the vest to the person and a flanged under portion that protrudes inwardly toward the person for engagement below both the lowest rib and the inverted U-shaped area of the rib cage. U.S. Pat. No. 4,569,340 was issued on Feb. 11, 1986 on such a vest.
While such vests have been utilized for many persons and have proved quite successful, all of the vests to date have required overhead support of the vest. This is a drawback in that such devices are large and cumbersome and are best utilized in a hospital or clinic setting.
U.S. Pat. No. 5,195,949 discloses a traction seating device which includes a pair of pivotal arm assemblies on which are mounted torso embracing members. Beneath the torso engaging members is a seat. The person using the traction seating device is able to transfer weight from the seat to the torso embracing members by lowering the seat.
However, to date there has sometimes been problems with adjusting the seat while the person is utilizing the device. It is sometimes difficult for the adjustable strap, which is attached to the seat, to be lowered in a controlled manner. The seat and strap should allow for a smooth reduction of weight bearing on the strap to allow for further unloading. This can either be done uniformly (both sides simultaneously) or differentially (with side-to-side variation).
A person can become adept at lowering the strap of the prior art design and control the actions smoothly. The seat typically starts out at a higher level when the person enters the axial unloading device and then it is gradually lowered to allow for more unloading. After each loading session, it is necessary that the strap be adjusted back to the starting position. The starting position is normally the same for the beginning of each unloading session. For certain persons, specifically those with reduced hand and finger strength, low coordination skills and/or oversize or large hips all of which can impede the proper lowering of the strap, the prior art device may be very difficult to use. These physical constraints may render the traction device unusable, because the person cannot effectively reduce the weight on the strap.
Accordingly, the present invention addresses this problem associated with the prior art and provides for a seat member whose height may be easily adjusted while the traction device is in use.